Mouse Tweaks replaces the standard RMB dragging mechanic, adds two new LMB dragging mechanics and an ability to quickly move items with the scroll wheel. Everything can be enabled and disabled in the configuration file or in Forge's mod options menu.
The mod is open-source!Configuration file: .minecraft/config/MouseTweaks.cfg

RMB Tweak

Very similar to the standard RMB dragging mechanic, with one difference: if you drag over a slot multiple times, an item will be put there multiple times. Replaces the standard mechanic if enabled.Configuration setting: RMBTweak=1

Hold your right mouse button:

Drag your mouse around the crafting grid:

You can drag your mouse on top of existing items:

LMB Tweak (with item)

Lets you quickly pick up or move items of the same type.Configuration setting: LMBTweakWithItem=1

Hold your left mouse button to pick up an item:

Drag your mouse across the inventory. Items of the same type will be picked up:

LMB Tweak (without item)

Hold shift, then hold your left mouse button:(Mouse cursor is not visible for some reason)

Drag your mouse across the inventory. Items will get "shift-clicked":(Mouse cursor is not visible for some reason)

Wheel Tweak

Scroll to quickly move items between inventories. When you scroll down on an item stack, its items will be moved one by one. When you scroll up, items will be moved into it from another inventory.Configuration setting: WheelTweak=1

Configuration setting: WheelSearchOrder=1
When you scroll up, the mod will search for items from last to first (when this is set to 1) or from first to last (when this is set to 0).

Configuration setting: WheelScrollDirection=0
Set this to 1 to invert the default scroll actions. So, when set to 1, scrolling down will pull the items and scrolling up will push the items.

Set this to 2 to enable the inventory position aware scrolling. Scrolling up will push the items into the other inventory if it's above the selected slot, or pull items from the other inventory if it's below the selected slot. Vice versa for scrolling down.

Configuration setting: OnTickMethodOrder=Forge, LiteLoader
Mouse Tweaks can use multiple APIs for an OnTick method that it requires. You can use this setting to control the API it prefers. This shouldn't really matter at all. If a method isn't supported (for example, you don't have the API installed) the mod will proceed to check the next ones.

Compatibility

Mouse Tweaks is compatible with everything based on GuiContainer (as long as the behavior isn't changed too much).

If your GUI isn't based on GuiContainer, or if you want to improve compatibility (making Mouse Tweaks ignore some slot, for example), take a look at the API documentation.

Old installation instructions

1.6: How to install mods into the JAR - tutorial by xisumavoid

There are multiple ways of installing Mouse Tweaks:

Extract the Mouse Tweaks zip-file into your Minecraft JAR (don't forget to remove the META-INF folder!) - compatible with LiteLoader and other mods that don't overwrite the same class file.

Install at least one of these: ModLoader, Minecraft Forge, LiteLoader and drop the mod's zip-file into your mods folder. Your mods folder is either in your .minecraft folder, or in your .minecraft/versions/<Minecraft version> folder. Please note that if you are using just LiteLoader by itself (without ModLoader or Forge) you will need to change the extension of the Mouse Tweaks' zip-file from .zip to .litemod.

Install either ModLoader or Minecraft Forge.

Drop the mod's zip-file into your mods folder.

NoModLoader:

Open your minecraft.jar.

Delete the META-INF folder.

Open the Mouse Tweaks' zip-file.

Drag the class file from the Mouse Tweaks zip-file into your minecraft.jar.

Changelog

Later changelog can be found on CurseForge.2.4.3:
[FIXED] LiteLoader compatibility.
[FIXED] The mod can now be loaded by either Forge or LiteLoader.
[CHANGED] ForceForgeOnRenderTick config setting to OnTickMethodOrder.2.4.2:
[FIXED] A crash that occurs if you spin the wheel down too fast on a stack which has a low amount of items in it.2.4.1:
[FIXED] Fixed LiteLoader compatibility. Still requires Forge.
[CHANGED] Changed ForceModLoader to ForceForgeOnRenderTick.2.4.0:
Update to Minecraft 1.7.2.
Works only with Forge for now.2.3.4:
Update to Minecraft 1.6.4.2.3.3 / 2.0.3:
...and a bunch more stuff.2.3.2 / 2.0.2:
[FIXED] A bunch of stuff that I accidentally messed up.2.3.1 / 2.0.1:
A pretty large rewrite to improve performance and compatibility.
The mod is now open-source!
[ADDED] Compatibility with Forestry.
[ADDED] Config setting WheelSearchOrder. If this is 1, when you scroll up, the mod tries to pull from the last applicable stack in the inventory. If 0, from the first. Defaults to 1, because when your inventory is sorted, the 'incomplete' stack is the one on the left.
[ADDED] More compatibility with standart Minecraft inventories.
[CHANGED] Version numbers. Basically now there will be numbers instead of letters, so 2.3.1 instead of 2.3b.2.2b / 2.0b:
[ADDED] Wheel tweak, which operates like the one that used to be in NotEnoughItems, but was removed in 1.5.2 for some reason.
[ADDED] ForceModLoader config setting, generally advised to be turned off at all times.
[CHANGED] The mod will now add missing config options to the config file.2.2:
Update to Minecraft 1.6.2.
[CHANGED] Removed some unused code, may fix incompatibility with some mods, although I am not sure.2.1:
Update to Minecraft 1.6.1.2.0:
Almost a complete rewrite.
[CHANGED] Merged normal and NoModloader versions together. Now both work as fast as the NoModloader one, the config file is checked every time you open some inventory.
[CHANGED] Now you can install Mouse Tweaks however you want.
[CHANGED] Config file is now called not mod_MouseTweaks.cfg, but simply MouseTweaks.cfg.
[ADDED] Compatibility with Minecraft Forge (mcmod.info file), LiteLoader (version.txt and a new class file), Better Than Wolves (install Mouse Tweaks into the JAR).1.2:
Update to Minecraft 1.5.2.1.1c:
Really fixed that crash bug. (lol)1.1b:
Fixed a crash bug that occurs ocasionally.1.1:
Update to Minecraft 1.5.1.1.0c:
[FIXED] Bugs regarding right clicking items.1.0b:
[FIXED] Compatibility with Minecraft Forge.
[FIXED] Right Shift not working for Shift + Drag functionality.1.0:
Update to Minecraft 1.5.
[ADDED] A config file in NoModloader version. It is the same one as in ModLoader version. If the config does not exist, it will be created automatically and you will receive a chat notification.
[CHANGED] Mouse Tweaks checks the settings from the config file every time you open an inventory (NoModloader version only for now).BETA 4:
[FIXED] Compatibility with Forestry.
[FIXED] Mouse Tweaks should now just not work in custom inventories instead of crashing.BETA 3:
Update to Minecraft 1.4.6.
Added NoModloader versions.
[FIXED] Right Click + dragging out of inventory and into the same inventory slot not adding item (not very useful).BETA 2:
[ADDED] Config file.
[ADDED] Shift + Left Click dragging without item.

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